Predator 212 Hemi Build

[thebozz]

Hello all! it's been a while since I've posted last but here goes. I have recently bought a Harbor Freight Predator 212 engine with the hemispherical head on it. This will be going in a shopping cart that a friend and I "borrowed" from my local grocery store. So far I have bought and plan on installing a number of items for this engine. Here is the list I have as of right now (All of these parts come from ARC Racing): Air Filter Adapter Clone/GX200, DJ-1103 Cam Clone Dyno BP-2, DJ-1225R Carburetor, Stock RuiXing, DJ-1345 BSP Carb Stud, 6899 Angled Air Filter, DJ-1056 Valve Spring 26lb HP 'White Stripe', 6254 ARC Billet Rod, HF Predator 212cc 3.308 (std length), DJ-114X ARC Top Plate/Throttle Station, DJ-124xxx GX/Clone Main Jet Drilled to 0.036, and DJ-1251 BSP/Clone GX140 "E" Tube. I am also going to fabricate my own straight pipe. My questions are as follows: What do you recommend I have as far as my emulsion tube and main jet goes in the RuiXing carb? Becuase I bought what seems to be pretty standard for an hi-flow air filter and open header but I'm not entirely sure what would be optimal for my BP2 Cam. My other question is that the cam says "Ignition Timing: 30 Deg BTDC" does that mean that I should time my flywheel to 30 degrees BTDC? I want to buy a flywheel but it says that it is advanced 32 degrees BTDC. So what flywheel should I buy and how do I time it to match the carb jets and camshaft? Any comments are appreciated and IF YOU SEE ANY ISSUES WITH MY CURRENT LIST OF MODS, PLEASE LET ME KNOW! I WANT TO HEAR EVERYONE'S OPINIONS!

 

[Poboy kartman]

Weird....the BP2 specs I Gooogled said 32°BTDC?

Regardless, you should be fine. You could always get a 2° advanced key and install it backwards...but I'd double check on that cam.

 

[thebozz]

Here's the link to the ARC page for the BP-2 Cam. http://www.arcracing.com/dj-1103p-predator-bp-2-cam/
And here is the link to the flywheel I am contemplating on getting:
http://www.arcracing.com/6626-arc-kohler-ch270-new-predator-212-billet-flywheel/
Another question, what does it mean by this "Now featuring 8 degrees timing advance built into the keyway. 32 degrees BTDC." And do my list of mods all look alright? No red flags?

---------- Post added at 12:22 AM ---------- Previous post was at 12:17 AM ----------

Also, I'm curious what jets you think I should run, I'm pretty much at sea level here.

 

[Poboy kartman]

Ahhhh....there's the difference! Did you notice in that link you supplied it says "does not fit hemi? "

I was looking at the BP2 for $39 from DynoCams that does!

Oh...and the stock timing on the Predator is 24°BTDC ....so it means the key is cut 8° more advanced or 32°BTDC.

 

[thebozz]

Ah shoot..... I was looking at a ton of cams when I was shopping. I really should have paid more attention to that... What cam would you suggest that I run? the mod2 Cheater cam?

 

[Poboy kartman]

Well....I'll wait for someone else that messes with these more to advise you. ARC does have a BP2 that fits the hemi..but it's also for 30°? The DynoCams BP2 is a 32° BTDC cam. A lot of guys run the mod2, so, like I said, I'll defer to more qualified help....which this forum is full of.

 

[thebozz]

Now I feel like an idiot. I posted the wrong link to the BP2 cam, this is the one I bought: http://www.arcracing.com/dj-1103-cam-clone-dyno-bp-2/

 

[Poboy kartman]

That's cool...that's the one I was talking about....so...we're back to square one. I missed that you had already bought all that stuff. I think you might be alright running that cam with a 32°flywheel....(I can't recall a 30° ?)

Anyway tomorrow they'll be more guys around to help!

 

[thebozz]

I can't believe I almost canceled my order for the cam because I didn't look carefully enough. I'm glad I cleared that up. Thank you for the responses. I really do appreciate it.

 

[chancer]

Wheres Bob???

 

[bob58o]

Wheres Bob???

I'm looking for machinists and research how carbs work!

---------- Post added at 10:04 AM ---------- Previous post was at 10:02 AM ----------

Carry On!

The gx140 E-Tube and 0.036" Main Jet is a good place to start.
If you do some research you can find out how much you have to shave off the stock key to get a 6 degree woodruff key.
Or I have seen 2,4,6,8 precut keys online for cheap (depends on shipping)
I have seen adjustable flywheels as well.

The Cam you choose doesn't doesn't have that much lift, but a lot of duration. If you are rich (EDIT: financially, not fuel/air mix lol) you can get some 1.2 ratio rockers.

Let me look for the info about keys.

What size tires and gearing are you planning on using? Using a clutch or Torque Converter.

---------- Post added at 10:08 AM ---------- Previous post was at 10:04 AM ----------

$8 (not cheap) 6*key https://www.ombwarehouse.com/6-Degree-Offset-key.html?category_id=1632

 

[Poboy kartman]

Cheaper than a flywheel! But if he's going to get a flywheel anyway....I suggested he get the 2° key and install it the other way.

 

[bob58o]

And by no means am i anything above a beginner, i have just been buying parts for same engine too!

---------- Post added at 10:24 AM ---------- Previous post was at 10:20 AM ----------

Cheaper than a flywheel! But if he's going to get a flywheel anyway....I suggested he get the 2° key and install it the other way.

Are you baiting me here for a timing joke? My head hurts and I'm having a hard time visualizing this. 2 degree keys are same price as 6 degree keys, no?

---------- Post added at 10:27 AM ---------- Previous post was at 10:24 AM ----------

Oh a 32 degree flywheel with a backwards 2 degree key. Not positive, I didn't get a flywheel. I like to live dangerously - Jake Bond from State Farm



---------- Post added at 10:29 AM ---------- Previous post was at 10:27 AM ----------

Actually I take back all my advice....
Much better advice is call Jody at ARC racing and ask him anything you want to know!

 

[Poboy kartman]

Now you got it...the billet flywheel at ARC has 32° of timing. Either he just keeps the stock one and buys the 6° key...or the billet with a 2° key.

 

[bob58o]

Yes I wasn't sure if all the flywheels had a 32 degree advance built in. If you can use a timing light, you can lap the flywheel to the crank and do away with the key.
(I'm assuming a standard key is used with these flywheels, but haven't actually had one).

"When lapping an aluminum flywheel, I use a steel or cast iron flywheel and lap it to the crank. Then put your aluminum flywheel on and lap it to the crank. What happens is if you try to lap an aluminum flywheel first, it is to soft and won't cut the crank which is steel. I've done it this way for years and never had a problem with spinning one. Good luck....Oh, I am assuming you are using an aluminum flywheel. I wouldn't use any lock tite on it. Especially red."

If you call ARC, you will get someone on the phone easily. Ask a confusing question to the first person you get and then ask to speak to Jody if possible. He is commonly on forums giving advice and I have spoken to him multiple times. I basically went over my whole shopping kart with him before I placed the order. No wait... it is cart this time.

Is this build a go kart or go cart? Jody will need to know, lol

 

[thebozz]

I'm loving all of these suggestions
There is a racing go kart place next to my house called CMC and I have talked to the guy there a fair amount about this build. By the way, if any of you are in the Beaverton/Tigard area in Oregon, make sure to check this place out, they are EXTREMELY helpful. I just bought this flywheel http://www.arcracing.com/6626-arc-kohler-ch270-new-predator-212-billet-flywheel/. I will also buy a 2 degree timing key and install it backwards to get my 32 degree advanced flywheel retarded by 2 degrees to approach the 30 degree suggested ignition timing according to my camshaft. I am also about to buy some genuine Honda valves to replace the stock Predator ones but I am not sure if they will fit because I don't want to change the size of what I already have. They guy at CMC is checking on the sizing and if they are compatible tomorrow morning for me. And in response to the 1.2:1 rockers comment, How much more lift in the valves am I looking at if I install these? And I do plan on lapping the stock flywheel to the crank, then the billet flywheel, thank you for that suggestion. I do think I am still going to use a key, however.

---------- Post added at 09:56 PM ---------- Previous post was at 09:51 PM ----------

I'm looking for machinists and research how carbs work!

---------- Post added at 10:04 AM ---------- Previous post was at 10:02 AM ----------

Let me look for the info about keys.

What size tires and gearing are you planning on using? Using a clutch or Torque Converter.

---------- Post added at 10:08 AM ---------- Previous post was at 10:04 AM ----------

$8 (not cheap) 6*key https://www.ombwarehouse.com/6-Degree-Offset-key.html?category_id=1632

My tires are 10" in diameter, I plan on using a 12 tooth clutch to a 65 tooth rear sprocket. No jackshafts or anything. And I believe, as far as timing keys go, every .001 you shave off of the key is equal to 1 degree advance or retard.

---------- Post added at 09:58 PM ---------- Previous post was at 09:56 PM ----------

What is the next part to on these motors to "govern" the rpm? I have a billet connecting rod, 26lb springs, working on better valves, have a new cam, billet flywheel, new jets and carb, etc. What is next on the list to get me to rev sky high?

 

[Poboy kartman]

You're probably good on the gearing.....it's a bit steep, but your tires are small. Keep an eye on your clutch heat....you may need a 72 tooth sprocket if it starts burning up clutches.

 

[thebozz]

That is another issue, a friend and I are building this thing together and (go figure), I'm in charge of the engine and he bought the clutch. Do you think that this clutch will hold up? http://www.amazon.com/CENTRIFUGAL-C...TF8&qid=1462936091&sr=8-1&keywords=3/4+clutch
Also we can't go too much larger on the sprocket or it might be taller than the tires.

---------- Post added at 10:12 PM ---------- Previous post was at 10:09 PM ----------

Also, just out of curiosity, what is the max RPM that any of you have seen the hemi predator 212 reach? And what is the largest amount of torque and horsepower that one can juice out of these things? I'm just curious what the potential of these engines are.

 

[Poboy kartman]

Well...it either will or wont....you may not be able to go much larger on the axle sprocket....but you also can't go smaller on the clutch...(without. some weird stuff) .... so run it as is and monitor that clutch....better to burn up a $20 clutch than a $100 one!

 

[thebozz]

Very true. Now on to brakes. What do you suggest? And I will upload some pictures pretty soon, all the parts come in on the 12th except the flywheel, that doesn't come in until next Tuesday. And when is all said and done, I am going to be taking this beast to a dyno to see what kind of numbers I can get out of this thing.

---------- Post added at 10:43 PM ---------- Previous post was at 10:26 PM ----------

And if my tank is higher than the carb, do I need a fuel pump?